From 9c6d039ad3aed2d65fe6a8facd3268fae4001439 Mon Sep 17 00:00:00 2001
From: sahanashenoy <sahana291996@gmail.com>
Date: Fri, 5 Oct 2018 16:10:48 +0530
Subject: [PATCH] subsequences of a string in Java

---
 SubSequences.java | 43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 SubSequences.java

diff --git a/SubSequences.java b/SubSequences.java
new file mode 100644
index 0000000..9062633
--- /dev/null
+++ b/SubSequences.java
@@ -0,0 +1,43 @@
+/*This is a Recursive Algorithm for finding a subsequences of a string in Java*/
+
+/*A String is a subsequence of a given String, that is generated by deleting some character of a given string without changing its order.
+
+
+Eg:input: abc
+   o/p:a, b, c, ab, bc, ac, abc
+*/
+
+public class SubSequences {
+	
+	private static String[] findSequences(String str) 
+	{
+		if(str.length()==0)
+		{
+			String ans[]= {""};
+			return ans;
+		}
+		String smallAns[]=findSequences(str.substring(1));
+		String ans[]=new String[2*smallAns.length];
+		int k=0;
+		for(int i=0;i<smallAns.length;i++)
+			ans[k++]=smallAns[i];
+		
+		for(int i=0;i<smallAns.length;i++)
+			ans[k++]=str.charAt(0)+smallAns[i];
+		
+		return ans;
+	}
+
+	public static void main(String[] args) {
+	
+		String str="abc";
+		String ans[]=findSequences(str);
+		for(int i=0;i<ans.length;i++)
+			System.out.println(ans[i]);
+
+	}
+
+	
+
+}
+